Four computers and external media were seized, which contained images of child sexual abuse, the OPP said.

"If we go into a house and execute a search warrant, we will take all of the computers in the house. One of the houses had two computers in it," said Insp. Scott Naylor, head of the OPP's CSES.

External media is classified as thumb drives and other external hardware.

"We take anything that has access to the Internet and anything we locate child pornography on," Naylor said.

Cody Rolston, 24, of Nottawasaga Street, has been charged with two counts of possession of child pornography, two counts of making available child pornography and one count of accessing child pornography. He was remanded into custody at a bail hearing Wednesday.

Sasa Elez, 20, of High Street, has been charged with four counts of possession of child pornography and three counts of making available child pornography. He was released from police custody at a bail hearing Wednesday.

Adam Kramshoj, 25, of Coldwater Road West, has been charged with two counts of possession of child pornography, one count of making available child pornography and one count of possession of a controlled substance.

Police executed his search warrant at the residence Wednesday, but Kramshoj was not home at the time. He turned himself in to police Thursday. He then had a bail hearing Thursday. The outcome was not available Thursday.

Naylor said the three cases are separate.

"They are not known to each other," he said.

The age of the young adults charged in Orillia does not surprise Naylor.

"We've even had teenagers in the past," he said.

"We've done provincewide sweeps before where we've had everybody from 14 years old to 70 years old."

Material is classified as child pornography when it involves people younger than 18.

In the past year and a half, Naylor has noticed worldwide offenders in child pornography becoming "younger and younger."

This is due to the increased accessibility offered by the Internet and social media, Naylor said.

"Trading child pornography used to be by plain manila envelope and all that kind of stuff," he said. "It makes it that much easier and that much more accessible for everyone."

The three Orillia men were located through an OPP-developed program called Ephex, which automatically gets in the middle of peer-to-peer child pornography file sharing, Naylor said.

The CSES moved to OPP General Headquarters in Orillia from a Toronto government building in early April 2010. The majority of Ephex was developed in Orillia by Joseph Versace, a program analyst who works in the CSES.

The program works by tracking all known images of child pornography the OPP has encountered in the past.

"Every time that we seize child pornography now, we put it in a database," Naylor said.

All the photos and movies have codes embedded in them that can be located automatically by Ephex when traded on a peer-to-peer file-sharing website, like LimeWire.

"(It's) how people trade music. They do it with child pornography as well," Naylor said.

The police then use IP addresses - unique numerical labels assigned to each individual computer network - to locate those engaged in the trade.

"We then go to a justice of the peace and swear... that we have a true belief the person from this IP address is trading child pornography," Naylor said.

Prior to going to the justice of the peace with their completed search warrant, police have to view the images to ensure it is child pornography and combine it with their known database of child pornography.

"All that does is provide you a lead," Naylor said.

"It doesn't do your work for you."

Ephex has been used by OPP since Versace completed the program 18 months ago. Prior to the automated system, the small OPP unit of 13 investigators was manually locating peer-to-peer child pornography sharing.

"It was a lot more complex and you had to be doing it live as people were doing the transmission of it," Naylor said.

The OPP have made Ephex available to other law-enforcement agencies around the globe.

"It benefits law enforcement, but what I like about it is this program puts us on the world stage," Naylor said, adding the automated program is the first of its kind.

For his creation, Versace won an OPP Accolade Award. He has also been nominated for an Ontario Amethyst Award for Outstanding Achievement by Ontario public servants.

"He is becoming one of the forefront innovators of tools in (the fight against) child pornography," Naylor said.

Versace has received emails informing him about kids being rescued from child exploitation through Ephex.

"My first one came on my 40th birthday. I was just over the moon about it," Versace said. "The job is hard enough. It's something to make things easier."

Versace, who has been with the CSES for fours years, is currently developing several other tools in the fight against child exploitation. Ephex is now being used by 200 agencies worldwide, including those in the United States, Romania, Australia, the United Kingdom and France.

"Law enforcement has limited resources," Naylor said, adding there are only 60 child pornography investigators in Ontario. "We share resources, we share finances, we share tools, traits and techniques. It's all for the good of the children."

Since its launch, Ephex has resulted in the execution of 1,000 search warrants. Six or seven of those, not including Wednesday's arrests, were in Orillia.

"There is a proliferation of child pornography on the Internet and Orillia is no worse or better than any other city in Ontario," Naylor said.

Det.-Const. Doug Lockhart, the most senior investigator on the CSES team, said the OPP use Ephex to isolate investigations to specific geographical areas.

"It enables us to monitor peer-to-peer networks for the opportunity of determining how much stuff's out there and where would our best target be to spend our time or go after," he said.

The system is not being run constantly throughout the entire province.

"If we were to run operational throughout the province of Ontario, it would task us with stuff we just would not be able to get to," Lockhart said. "That's how prevalent the offences of child pornography are in Ontario."

Four CSES OPP investigators work on peer-to-peer cases.

The unit also deals with online luring and reactive investigations.

"We're not going to arrest our way out of this problem," Lockhart said. "This is a societal problem. It's probably training and education."

TEENS, PARENTS MUST BE VIGILANT, OPP SAY

Teenage girls taking photos of themselves or allowing others to take photos of them is one of the largest problems facing the OPP's Child Sexual Exploitation Section (CSES).

"Once that image gets out there, it's always out there," Insp. Scott Naylor, who leads the section, said this week. "It's forever and ever and ever."

The CSES receives approximately five calls each week from parents trying to get the images of their daughters off the Internet.

"There is nothing we can do about it," Naylor said. "It's gone."

If the person in the photo is younger than 18, it is considered child pornography.

"They could be trading child pornography all over the place," Naylor said.

Naylor encourages parents to pay more attention to what their children are doing online and with their cellphone cameras. He said computers should be kept in an open space in the home.